For a 3-day self-drive trip from Italy to Switzerland in September, the best route focuses on the Ticino and Central Switzerland regions. September is the 'Golden Season'—mountain passes are still open, the summer crowds have thinned, and you may witness traditional Alpine cattle descents (Alpabzug).
This route starts from Northern Italy (Milan/Lake Como) and hits Switzerland's most iconic landscapes.
Day 1: Departure from Italy to Lugano & Bellinzona
Day 2: The St. Gotthard Pass to Lucerne
Day 3: Mount Titlis & Scenic Return via Valle Verzasca
If you prefer high-altitude glamour over cities, drive through Chiavenna (Italy) and up the Maloja Pass into St. Moritz.